Olfactory bulb (OB) ablations induce massive cell death among olfactory neurons (ORNs) and an expansion of the population of mitotic basal cells (BC). Within a week after bulbectomy new neurons are generated. As the ORN population grows, the number of mitotic BC decrease. To determine the mechanism for the regulation of OE regeneration, I am using microarray technology to analyze the dynamics of gene expression in OE from bulbectomized mice. I am in the process of performing several time-course studies to identify genes that are tightly correlated with regeneration. OE cRNA from bulbectomized mice are being used to probe an Affymetrix mouse gene chip. Genes found to be tightly correlated with the regenerating OE will be further analyzed for expression patterns. Once an expression pattern is identified to be appropriate for a potential role in regeneration, gene function will be perturbed using commercial reagents and/or retrovirus in in vivo experimental paradigms. [unreadable] [unreadable]